Very small question, but I've just changed from a Sony to a Kindle so I was converting all of my books to send across. I noticed that when I click "Convert Books" the "Output Format" in the top right corner of the window is set by default to ePub. Is there a way to change that so I don't have to change it to Mobi every time? I've done a search on the forum and couldn't see the answer. Apologies if it has been answered.

You might want to consider AZW3 instead of Mobi especially if any of your ePub's have any advanced formatting or embedded fonts you want to keep. Provided the Kindle you're using isn't an old Kindle 1 or Kindle 2 it will support AZW3/KF8. Not that Mobi isn't fine for most regular narrative style books.